Human Anaplasmosis Statistics
From 1995 to 2010, 2,638 cases of human anaplasmosis (HA) (formerly known as human granulocyctic ehrlichiosis) were reported in Minnesota. A record number of 720cases were reported in 2010 (16.9 cases per 100,000 population). The median number of 322 cases (range 139-322) reported from 2004 to 2010 is also considerably higher than the median number of cases reported annually from 1996 to 2003 (median 56, range 14-149).
The number of anaplasmosis cases has been increasing since the first cases of HA were reported in Minnesota in the mid-1990s. A variety of factors, including increasing physician awareness, increasing infection rates in ticks, and expanding tick distribution, may have led to this trend.
The HA cases in 2010 ranged in age from 2 to 92 years; the median age (57 years) was greater than that of Lyme disease (39 years). In 2010, 59% of HA cases were male.
On this page:
Annual summaries
Charts and graphs
Maps
Annual Summary Statistics
- Anaplasmosis, 2010
Minnesota Department of Health, Disease Control Newsletter;
Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2010.
- Anaplasmosis, 2009
Minnesota Department of Health, Disease Control Newsletter;
Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2009.
- Anaplasmosis, 2008
Minnesota Department of Health, Disease Control Newsletter;
Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2008.
- Anaplasmosis, 2007
Minnesota Department of Health, Disease Control Newsletter;
Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2007.
- Anaplasmosis, 2006
Minnesota Department of Health, Disease Control Newsletter;
Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2006.
- Anaplasmosis, 2005
Minnesota Department of Health, Disease Control Newsletter;
Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2005.
- Anaplasmosis, 2004
Minnesota Department of Health, Disease Control Newsletter;
Annual Summary of Communicable Diseases Reported to the Minnesota Department of Health, 2004.
Charts and Graphs
- Reported Cases of Human Anaplasmosis in Minnesota by Year
Graph showing the number of reported human anaplasmosis in Minnesota by year.
- Reported Cases of Human Anaplasmosis in Minnesota by Month of Onset
Graph showing the percent of cases of human anaplasmosis by month of onset.
Maps
Most HA cases report likely exposure to blacklegged ticks in the same east-central and north-central Minnesota counties where the risk of Lyme disease is greatest.
- High Risk Areas for Tick-borne Diseases in Minnesota
A map that shows counties of highest Tick-borne risk in Minnesota.



